Insects

17 pages, 1301 KiB

Open AccessArticle

Impact of the Addition of Tenebrio molitor and Hermetia illucens on the Physicochemical and Sensory Quality of Cooked Meat Products

by Barbara Lemke, Lisa Siekmann, Nils Th. Grabowski, Madeleine Plötz and Carsten Krischek

Insects 2023, 14(5), 487; https://doi.org/10.3390/insects14050487 - 22 May 2023

Cited by 4 | Viewed by 1653

Abstract

The use of proteins from insects, plants, microalgae, fungi or bacteria as an alternative to proteins of animal origin such as meat, fish, eggs or milk can meet the worldwide protein demand in the future. As the consumption of whole insects might be [...] Read more.

The use of proteins from insects, plants, microalgae, fungi or bacteria as an alternative to proteins of animal origin such as meat, fish, eggs or milk can meet the worldwide protein demand in the future. As the consumption of whole insects might be problematic or unacceptable for many consumers, especially in European countries, the use of homogenized insects or protein extracts from insects for the production of products might be a possibility to overcome general acceptability problems. However, the quality criteria of these products have to be comparable with consumers’ expectations with regard to known products. Therefore, in the present study, we produced a meat product, replaced 10% and 20% of the pork with homogenized larvae of Tenebrio molitor and Hermetia illucens, and determined different physicochemical and sensory parameters at production and during modified atmosphere storage for 21 days. Additionally, the alteration of different bacteria species during this storage was analyzed in challenge tests. After production, the addition of insects resulted in higher cooking losses and pH values in the products with 20% insects, higher pH and yellowness, lower lightness, protein and hardness results in the Hermetia products, as well as higher yellowness and lower protein and hardness values in the cooked meat products with Tenebrio molitor. During modified atmosphere storage, the color differences principally remained, whereas the concentrations of inoculated Bacillus cereus, Listeria monocytogenes and Escherichia coli were not influenced by the addition of insects to the cooked meat products. The sensory results of the insect products, especially at higher concentrations and with Hermetia illucens, worsened during modified atmosphere storage. The addition of homogenized insect larvae, especially at higher concentrations and particularly of Hermetia illucens, influences different physicochemical and sensory parameters of the cooked meat products. Full article

(This article belongs to the Topic Edible Insects as Feed and Food: Opportunities and Challenges)

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17 pages, 2710 KiB

Open AccessArticle

Circadian Activity and Clock Genes in Pachycrepoideus vindemmiae: Implications for Field Applications and Circadian Clock Mechanisms of Parasitoid Wasps

by Ziwen Teng, Mengran Huo, Yanan Zhou, Yuqi Zhou, Yunjie Liu, Yan Lin, Qi Zhang, Zhiqi Zhang, Fanghao Wan and Hongxu Zhou

Insects 2023, 14(5), 486; https://doi.org/10.3390/insects14050486 - 22 May 2023

Viewed by 1286

Abstract

Despite the importance of circadian rhythms in insect behavior, our understanding of circadian activity and the molecular oscillatory mechanism in parasitoid wasp circadian clocks is limited. In this study, behavioral activities expected to be under the control of the endogenous circadian system were [...] Read more.

Despite the importance of circadian rhythms in insect behavior, our understanding of circadian activity and the molecular oscillatory mechanism in parasitoid wasp circadian clocks is limited. In this study, behavioral activities expected to be under the control of the endogenous circadian system were characterized in an ectoparasitoid wasp, Pachycrepoideus vindemmiae. Most adults exhibited emergence between late night and early morning, while mating only occurred during the daytime, with a peak at midday. Oviposition had three peaks in the early morning, late day, or early night and late night. Additionally, we identified eight putative clock genes from P. vindemmiae. The quantitative PCR (qPCR) results indicate that most clock genes showed significant rhythmic expressions. Our comparative analysis of clock genes in P. vindemmiae and 43 other parasitoid wasps revealed that none of the wasps possessed the timeless and cry1 genes commonly found in some other insect species, suggesting that the circadian clock system in parasitoid wasps is distinct from that in other non-Hymenoptera insects such as Drosophila. Thus, this study attempted to build the first hypothetical circadian clock model for a parasitoid wasp, thus generating hypotheses and providing a platform for the future functional characterization of P. vindemmiae clock genes as well as those of other parasitoid wasps. Finally, these findings on P. vindemmiae circadian activity will aid the development of effective field release programs for biological control, which can be tested under field conditions. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

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15 pages, 3887 KiB

Open AccessArticle

Nine Mitochondrial Genomes of Phasmatodea with Two Novel Mitochondrial Gene Rearrangements and Phylogeny

by Yani Yuan, Lihua Zhang, Ke Li, Yuehuan Hong, Kenneth B. Storey, Jiayong Zhang and Danna Yu

Insects 2023, 14(5), 485; https://doi.org/10.3390/insects14050485 - 22 May 2023

Cited by 1 | Viewed by 1445

Abstract

The classification of stick and leaf insects (Order Phasmatodea) is flawed at various taxonomic ranks due to a lack of robust phylogenetic relationships and convergent morphological characteristics. In this study, we sequenced nine new mitogenomes that ranged from 15,011 bp to 17,761 bp [...] Read more.

The classification of stick and leaf insects (Order Phasmatodea) is flawed at various taxonomic ranks due to a lack of robust phylogenetic relationships and convergent morphological characteristics. In this study, we sequenced nine new mitogenomes that ranged from 15,011 bp to 17,761 bp in length. In the mitogenome of Carausis sp., we found a translocation of trnR and trnA, which can be explained by the tandem duplication/random loss (TDRL) model. In the Stheneboea repudiosa Brunner von Wattenwyl, 1907, a novel mitochondrial structure of 12S rRNA-CR1-trnI-CR2-trnQ-trnM was found for the first time in Phasmatodea. Due to the low homology of CR1 and CR2, we hypothesized that trnI was inverted through recombination and then translocated into the middle of the control region. Control region repeats were frequently detected in the newly sequenced mitogenomes. To explore phylogenetic relationships in Phasmatodea, mtPCGs from 56 Phasmatodean species (composed of 9 stick insects from this study, 31 GenBank data, and 16 data derived from transcriptome splicing) were used for Bayesian inference (BI), and maximum likelihood (ML) analyses. Both analyses supported the monophyly of Lonchodinae and Necrosciinae, but Lonchodidae was polyphyletic. Phasmatidae was monophyletic, and Clitumninae was paraphyletic. Phyllidae was located at the base of Neophasmatodea and formed a sister group with the remaining Neophasmatodea. Bacillidae and Pseudophasmatidae were recovered as a sister group. Heteroptergidae was monophyletic, and the Heteropteryginae sister to the clade (Obriminae + Dataminae) was supported by BI analysis and ML analysis. Full article

(This article belongs to the Section Insect Molecular Biology and Genomics)

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13 pages, 6034 KiB

Open AccessArticle

New Osmylopsychopid Taxa from the Middle Jurassic of Northeastern China (Neuroptera: Osmylopsychopidae)

by Xiaotian Liu, Dong Ren, Chungkun Shih and Yongjie Wang

Insects 2023, 14(5), 484; https://doi.org/10.3390/insects14050484 - 21 May 2023

Cited by 1 | Viewed by 1131

Abstract

One new genus with four new species sharing the similar character of a forewing length of ca. 10 mm, namely, Minipsychops spasulus gen. et sp. nov., Minipsychops polychotomus sp. nov., Minipsychops densus sp. nov., and Minipsychops unicus sp. nov., are described from the [...] Read more.

One new genus with four new species sharing the similar character of a forewing length of ca. 10 mm, namely, Minipsychops spasulus gen. et sp. nov., Minipsychops polychotomus sp. nov., Minipsychops densus sp. nov., and Minipsychops unicus sp. nov., are described from the Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia in China. These new insects can be attributed to Osmylopsychopidae for their distinctive configuration of costal space and the venations of RP1 and Cu. Compared with the typically medium to large body sizes of known osmylopsychopids, these new Middle Jurassic taxa of a particularly miniaturized lineage not only enrich the species diversity of Osmylopsychopidae, but also enhance our understanding of the historical evolution of these poorly known lacewings. Full article

(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)

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14 pages, 2435 KiB

Open AccessArticle

Rearing Host Dependency of Ovariole Number and Body Size in Campoletis chlorideae Uchida (Hymenoptera: Ichneumonidae)

by Liangheng Tian, Xiongya Wang, Yu Wang, Xiaohang Gu, Xin Li, Shiheng An, Xinming Yin and Sufen Bai

Insects 2023, 14(5), 483; https://doi.org/10.3390/insects14050483 - 20 May 2023

Cited by 1 | Viewed by 1040

Abstract

Campoletis chlorideae has great biocontrol potential against some major noctuid pests. In order to achieve the commercial development and utilization of C. chlorideae, this study focused on the effect of rearing host species and larval instars on the ovariole number and body [...] Read more.

Campoletis chlorideae has great biocontrol potential against some major noctuid pests. In order to achieve the commercial development and utilization of C. chlorideae, this study focused on the effect of rearing host species and larval instars on the ovariole number and body size of this wasp. Firstly, the morphology of the reproductive system and ovarioles of female wasps were observed. The number of ovarioles displayed great variability and asymmetry between bilateral ovaries. Moreover, the effect of four host species on ovariole number and body size of C. chlorideae were studied. The wasps had a larger ovariole number and body size when reared in Helicoverpa armigera. Additionally, the ovariole number and body size were larger when reared in the third instar larvae than in the first or second instar larvae of H. armigera. There was a strong positive correlation between the ovariole number and body size of C. chlorideae. The ovariole number and body size of the wasp could be improved under optimized artificial rearing conditions. According to these results, body size combined with ovariole number can be used as an important index to evaluate the quality of C. chlorideae. This study provides important clues for the development and application of biocontrol using C. chlorideae. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

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12 pages, 2326 KiB

Open AccessArticle

Bioefficacy of an Oil-Emulsion Formulation of Entomopathogenic Fungus, Metarhizium anisopliae against Adult Red Palm Weevil, Rhynchophorus ferrugineus

by Cheong Jia Lei, Raja Hasya Ilyana Raja Ahmad, Najihah Abdul Halim, Norhayu Asib, Azlina Zakaria and Wahizatul Afzan Azmi

Insects 2023, 14(5), 482; https://doi.org/10.3390/insects14050482 - 20 May 2023

Cited by 5 | Viewed by 1977

Abstract

The red palm weevil (RPW), Rhynchophorus ferrugineus, poses a severe threat to agro-industrial crops, particularly major cultivated palm species. Infestations result in economic losses due to reduced fruit quality and yield. The entomopathogenic fungus, Metarhizium anisopliae, has shown promise as a [...] Read more.

The red palm weevil (RPW), Rhynchophorus ferrugineus, poses a severe threat to agro-industrial crops, particularly major cultivated palm species. Infestations result in economic losses due to reduced fruit quality and yield. The entomopathogenic fungus, Metarhizium anisopliae, has shown promise as a potential biocontrol agent against the RPW. However, the use of an emulsion formulation of M. anisopliae for managing this serious insect pest has yet to be fully explored. The oil-emulsion formulation containing this entomopathogen may enhance the conidia’s stability, prolong its lifetime, and reduce the impact of heat stress or UV irradiation on the fungus. Therefore, this study aimed to investigate the bioefficacy of a new oil-in-glycerol emulsion formulation on mycoinsecticidal activity against RPW adults by direct and indirect bioassays. Results showed that conidia concentration was directly proportional to the RPW mortality percentage. The LT₅₀ of 8.183 days was achieved by the conidial formulation against RPW, with a significantly lower LC₅₀ (1.910 × 10⁵ conidia mL⁻¹) compared to the aqueous conidia suspension (LT₅₀ = 8.716 days; LC₅₀ = 7.671 × 10⁵ conidia mL⁻¹). Indirect bioassays revealed that the oil-in-glycerol emulsion had a disease-spreading ability that resulted in up to 56.67% RPW mortality. A zero E-value reading indicates that the DNA sequence being studied is highly similar to that of the fungal species M. anisopliae, which has been identified in the NCBI database. Although the new emulsion formulation has improved the efficacy and pathogenicity of M. anisopliae in vitro, it is important to also consider the fungal pathogen’s compatibility with other agricultural practices to prevent any loss of control efficiency in the actual usage environment. Full article

(This article belongs to the Special Issue Management of True Weevil (Curculionidae) Pests and Beneficial Species)

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14 pages, 1201 KiB

Open AccessArticle

A Novel Insect Overwintering Strategy: The Case of Mealybugs

by Rosa Vercher, Sandra González, Adrián Sánchez-Domingo and Juan Sorribas

Insects 2023, 14(5), 481; https://doi.org/10.3390/insects14050481 - 19 May 2023

Viewed by 1472

Abstract

Insects have limited ability to regulate their body temperature and have thus required a range of strategies to withstand thermally stressful environments. Under unfavorable winter conditions, insects often take refuge under the soil surface to survive. Here, the mealybug insect family was selected [...] Read more.

Insects have limited ability to regulate their body temperature and have thus required a range of strategies to withstand thermally stressful environments. Under unfavorable winter conditions, insects often take refuge under the soil surface to survive. Here, the mealybug insect family was selected for the study. Field experiments were performed in fruit orchards in eastern Spain. We used specifically designed floor sampling methods combined with fruit tree canopy pheromone traps. We found that in temperate climates, the large majority of the mealybugs move from the tree canopy to the roots during the winter, where they turn into belowground root-feeding herbivores to survive and continue underground the reproductive process. Within the rhizosphere, mealybugs complete at least one generation before emerging on the soil surface. The preferred area to overwinter is within 1 m in diameter around the fruit tree trunk, where more than 12,000 mealybug flying males per square meter can emerge every spring. This overwintering pattern has not previously been reported for any other group of insects showing cold avoidance behavior. These findings have implications at the winter ecology level but also at the agronomical level since treatments to control mealybug pests are, until now, only based on the fruit trees’ canopy. Full article

(This article belongs to the Section Insect Behavior and Pathology)

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14 pages, 613 KiB

Open AccessArticle

Herbicides Harm Key Orchard Predatory Mites

by Paul Bergeron and Rebecca Schmidt-Jeffris

Insects 2023, 14(5), 480; https://doi.org/10.3390/insects14050480 - 19 May 2023

Cited by 2 | Viewed by 1451

Abstract

The phytoseiid mites Galendromus occidentalis and Amblydromella caudiglans are critical for conservation biological control of pest mites in Washington State, U.S.A. apples. While the non-target effects of insecticides on phytoseiids are well described, research on herbicide effects is limited. Using laboratory bioassays, we [...] Read more.

The phytoseiid mites Galendromus occidentalis and Amblydromella caudiglans are critical for conservation biological control of pest mites in Washington State, U.S.A. apples. While the non-target effects of insecticides on phytoseiids are well described, research on herbicide effects is limited. Using laboratory bioassays, we examined lethal (female mortality) and sublethal (fecundity, egg hatch, larval survival) effects of seven herbicides and five adjuvants on A. caudiglans and G. occidentalis. The effects of mixing herbicides with recommended adjuvants were also tested to determine if the addition of an adjuvant increased herbicide toxicity. Glufosinate was the least selective herbicide tested, causing 100% mortality in both species. Paraquat caused 100% mortality in A. caudiglans and 56% mortality in G. occidentalis. Sublethal effects were significant for both species when exposed to oxyfluorfen. Adjuvants did not cause non-target effects in A. caudiglans. The non-ionic surfactant and methylated seed oil increased mortality and decreased reproduction in G. occidentalis. The high toxicity of glufosinate and paraquat for both predators is concerning; these are the primary “burn down” herbicide alternatives to glyphosate, which is decreasing in use due to consumer toxicity concerns. Field studies are needed to determine the extent to which herbicides disrupt orchard biological control, focusing on glufosinate, paraquat, and oxyfluorfen. Consumer preferences will need to be balanced with natural enemy conservation. Full article

(This article belongs to the Special Issue Biological Control in Temperate Orchards)

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14 pages, 501 KiB

Open AccessArticle

Application of Machine Learning Techniques to Discern Optimal Rearing Conditions for Improved Black Soldier Fly Farming

by John Muinde, Chrysantus M. Tanga, John Olukuru, Clifford Odhiambo, Henri E. Z. Tonnang and Kennedy Senagi

Insects 2023, 14(5), 479; https://doi.org/10.3390/insects14050479 - 19 May 2023

Viewed by 2599

Abstract

As the world population continues to grow, there is a need to come up with alternative sources of feed and food to combat the existing challenge of food insecurity across the globe. The use of insects, particularly the black soldier fly (BSF) Hermetia [...] Read more.

As the world population continues to grow, there is a need to come up with alternative sources of feed and food to combat the existing challenge of food insecurity across the globe. The use of insects, particularly the black soldier fly (BSF) Hermetia illucens (L.) (Diptera: Stratiomydiae), as a source of feed stands out due to its sustainability and reliability. Black soldier fly larvae (BSFL) have the ability to convert organic substrates to high-quality biomass rich in protein for animal feed. They can also produce biodiesel and bioplastic and have high biotechnological and medical potential. However, current BSFL production is low to meet the industry’s needs. This study used machine learning modeling approaches to discern optimal rearing conditions for improved BSF farming. The input variables studied include the cycle time in each rearing phase (i.e., the rearing period in each phase), feed formulation type, length of the beds (i.e, rearing platforms) at each phase, amount of young larvae added in the first phase, purity score (i.e, percentage of BSFL after separating from the substrate), feed depth, and the feeding rate. The output/target variable was the mass of wet larvae harvested (kg per meter) at the end of the rearing cycle. This data was trained on supervised machine learning algorithms. From the trained models, the random forest regressor presented the best root mean squared error (RMSE) of 2.91 and an R-squared value of 80.9%, implying that the model can be used to effectively monitor and predict the expected weight of BSFL to be harvested at the end of the rearing process. The results established that the top five ranked important features that inform optimal production are the length of the beds, feed formulation used, the average number of young larvae loaded in each bed, feed depth, and cycle time. Therefore, in that priority, it is expected that tuning the mentioned parameters to fall within the required levels would result in an increased mass of BSFL harvest. These data science and machine learning techniques can be adopted to understand rearing conditions and optimize the production/farming of BSF as a source of feed for animals e.g., fish, pigs, poultry, etc. A high production of these animals guarantees more food for humans, thus reducing food insecurity. Full article

(This article belongs to the Special Issue Breakthrough Technologies for Future Entomology)

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11 pages, 911 KiB

Open AccessArticle

Life Histories and Functional Responses of Two Predatory Mites Feeding on the Stored-Grain Pest Liposcelis bostrychophila Badonnel (Psocoptera: Liposcelididae)

by Weiwei Sun, Liyuan Xia and Yi Wu

Insects 2023, 14(5), 478; https://doi.org/10.3390/insects14050478 - 19 May 2023

Cited by 2 | Viewed by 1147

Abstract

Cheyletus malaccensis Oudemans and Cheyletus eruditus (Schrank) are predators of stored-grain pests in China. The psocid Liposcelis bostrychophila Badonnel is prone to outbreaks in depots. To assess the potential of large-scale breeding with Acarus siro Linnaeus and the biological control potential of C. [...] Read more.

Cheyletus malaccensis Oudemans and Cheyletus eruditus (Schrank) are predators of stored-grain pests in China. The psocid Liposcelis bostrychophila Badonnel is prone to outbreaks in depots. To assess the potential of large-scale breeding with Acarus siro Linnaeus and the biological control potential of C. malaccensis and C. eruditus against L. bostrychophila, we determined the development times of different stages at 16, 20, 24, and 28 °C and 75% relative humidity (RH) while feeding on A. siro, as well as the functional responses of both species’ protonymphs and females to L. bostrychophila eggs at 28 °C and 75% RH. Cheyletus malaccensis had a shorter development time and longer adult survival time than C. eruditus at 28 °C and 75% RH and could establish populations faster than C. eruditus while preying on A. siro. The protonymphs of both species showed a type II functional response, while the females showed a type III functional response. Cheyletus malaccensis showed a higher predation ability than C. eruditus, and the females of both species had a higher predation ability than the protonymphs. Based on the observed development times, adult survival times, and predation efficiency, Cheyletus malaccensis has much greater biocontrol potential than C. eruditus. Full article

(This article belongs to the Collection Stored-Product Pests: Biology, Ecology, Behavior and Integrated Management)

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12 pages, 1980 KiB

Open AccessArticle

Biocontrol of Xyleborus affinis (Curculionidae: Scolitinae) Females and Progeny by Beauveria bassiana (Hypocreales: Cordycipitaceae) in a Sawdust Artificial Diet Model

by Jesús E. Castrejón-Antonio, Patricia Tamez-Guerra, Nohemi García-Ortiz, Facundo Muñiz-Paredes, Juan Carlos Sánchez-Rangel and Roberto Montesinos-Matías

Insects 2023, 14(5), 477; https://doi.org/10.3390/insects14050477 - 19 May 2023

Viewed by 1182

Abstract

The ambrosia beetle Xyleborus affinis, recently reported affecting avocado trees in Mexico, represents one of the most widespread insects worldwide. Previous reports have shown that Xyleborus genera members are susceptible to Beauveria bassiana and other entomopathogenic fungus strains. However, their effect on [...] Read more.

The ambrosia beetle Xyleborus affinis, recently reported affecting avocado trees in Mexico, represents one of the most widespread insects worldwide. Previous reports have shown that Xyleborus genera members are susceptible to Beauveria bassiana and other entomopathogenic fungus strains. However, their effect on borer beetles’ progeny has not been fully investigated. The aim of the present study was to determine the insecticidal activity of B. bassiana on X. affinis adult females and their progeny in an artificial sawdust diet bioassay model. The B. bassiana strains CHE-CNRCB 44, 171, 431, and 485 were individually tested on females at concentrations ranging from 2 × 10⁶ to 1 × 10⁹ conidia mL⁻¹. After 10 d of incubation, diet was evaluated to count laid eggs, larvae, and adults. Insect conidia loss after exposure was determined by attached conidia to each insect after 12 h of exposure. The results showed that females’ mortality ranged between 3.4% and 50.3% in a concentration–response manner. Furthermore, we did not observe statistical differences among strains at the highest concentration. CHE-CNRCB 44 showed the highest mortality at the lowest concentration and reduced larvae and laid eggs at the highest concentration (p < 0.01). Strains CHE-CNRCB 44, 431, and 485 significantly decreased larvae, as compared with the untreated control. After 12 h, up to 70% of conidia was removed by the effect of the artificial diet. In conclusion, B. bassiana has the potential to control X. affinis adult females and progeny. Full article

(This article belongs to the Special Issue Production and Application of Insect Pathogens in Biological Pest Control)

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18 pages, 7319 KiB

Open AccessArticle

Climate Change Impacts on the Potential Distribution Pattern of Osphya (Coleoptera: Melandryidae), an Old but Small Beetle Group Distributed in the Northern Hemisphere

by Tong Liu, Haoyu Liu, Yongjie Wang and Yuxia Yang

Insects 2023, 14(5), 476; https://doi.org/10.3390/insects14050476 - 18 May 2023

Cited by 3 | Viewed by 1812

Abstract

Exploring the development of species distribution patterns under climate change is the basis of biogeography and macroecology. However, under the background of global climate change, few studies focus on how the distribution pattern and the range of insects have or will change in [...] Read more.

Exploring the development of species distribution patterns under climate change is the basis of biogeography and macroecology. However, under the background of global climate change, few studies focus on how the distribution pattern and the range of insects have or will change in response to long-term climate change. An old but small, Northern-Hemisphere-distributed beetle group Osphya is an ideal subject to conduct the study in this aspect. Here, based on a comprehensive geographic dataset, we analyzed the global distribution pattern of Osphya using ArcGIS techniques, which declared a discontinuous and uneven distribution pattern across the USA, Europe, and Asia. Furthermore, we predicted the suitable habitats of Osphya under different climate scenarios via the MaxEnt model. The results showed that the high suitability areas were always concentrated in the European Mediterranean and the western coast of USA, while a low suitability exhibited in Asia. Moreover, by integrating the analyses of biogeography and habitat suitability, we inferred that the Osphya species conservatively prefer a warm, stable, and rainy climate, and they tend to expand towards higher latitude in response to the climate warming from the past to future. These results are helpful in exploring the species diversity and protection of Osphya. Full article

(This article belongs to the Special Issue Climate Change and Insects)

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14 pages, 2324 KiB

Open AccessArticle

Predicting the Distribution of Sclerodermus sichuanensis (Hymenoptera: Bethylidae) under Climate Change in China

by Hui Gao, Qianqian Qian, Lijuan Liu and Danping Xu

Insects 2023, 14(5), 475; https://doi.org/10.3390/insects14050475 - 18 May 2023

Cited by 2 | Viewed by 1141

Abstract

Sclerodermus sichuanensis is the natural enemy of the longicorn beetle due to its strong attack ability and high parasitic rate. Its good resistance and fecundity make it have significant biological control value. The Maxent model and ArcGIS software were used to simulate the [...] Read more.

Sclerodermus sichuanensis is the natural enemy of the longicorn beetle due to its strong attack ability and high parasitic rate. Its good resistance and fecundity make it have significant biological control value. The Maxent model and ArcGIS software were used to simulate the current distribution of S. sichuanensis in China by combining the known distribution information and environmental variables and predict the suitable area of the 2050s (2041–2060) and 2090s (2081–2000) under three climate scenarios (SSP1-2.6, SSP2-4.5. and SSP5-8.5). The results showed that the Mean Diurnal Range (bio2), Min Temperature of the Coldest Month (bio6), Precipitation of the Warmest Quarter (bio18), and Max Temperature of the Warmest Month (bio5) were the key environmental variables affecting the distribution of S. sichuanensis. Southwest China and part of North China are the main concentrations of the current high-suitability areas of S. sichuanensis. The moderately suitable areas are concentrated in South China and Central China. Under the SSP5-8.5 scenario, the suitable area predicted in the 2050s will expand significantly to North China and Northwest China, with a total increase of 81,295 km². This work provides an essential reference for future research on S. sichuanensis and the application of forestry pest control. Full article

(This article belongs to the Special Issue Climate Change and Insects)

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12 pages, 974 KiB

Open AccessReview

Mechanisms of Neuroendocrine Stress Response in Drosophila and Its Effect on Carbohydrate and Lipid Metabolism

by Margarita A. Bobrovskikh and Nataly E. Gruntenko

Insects 2023, 14(5), 474; https://doi.org/10.3390/insects14050474 - 17 May 2023

Cited by 1 | Viewed by 1944

Abstract

Response to short-term stress is a fundamental survival mechanism ensuring protection and adaptation in adverse environments. Key components of the neuroendocrine stress reaction in insects are stress-related hormones, including biogenic amines (dopamine and octopamine), juvenile hormone, 20-hydroxyecdysone, adipokinetic hormone and insulin-like peptides. In [...] Read more.

Response to short-term stress is a fundamental survival mechanism ensuring protection and adaptation in adverse environments. Key components of the neuroendocrine stress reaction in insects are stress-related hormones, including biogenic amines (dopamine and octopamine), juvenile hormone, 20-hydroxyecdysone, adipokinetic hormone and insulin-like peptides. In this review we focus on different aspects of the mechanism of the neuroendocrine stress reaction in insects on the D. melanogaster model, discuss the interaction of components of the insulin/insulin-like growth factors signaling pathway and other stress-related hormones, and suggest a detailed scheme of their possible interaction and effect on carbohydrate and lipid metabolism under short-term heat stress. The effect of short-term heat stress on metabolic behavior and possible regulation of its mechanisms are also discussed here. Full article

(This article belongs to the Special Issue Insect Hormones, Metabolism, Immunity and Development)

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11 pages, 323 KiB

Open AccessArticle

Life Table Parameters of Tetranychus merganser Boudreaux (Acari: Tetranychidae) on Five Host Plants

by Ma. Teresa de Jesús Segura-Martínez, Salvador Ordaz-Silva, Agustín Hernández-Juárez, Rapucel Tonantzin Quetzalli Heinz-Castro, Sandra Grisell Mora-Ravelo and Julio César Chacón-Hernández

Insects 2023, 14(5), 473; https://doi.org/10.3390/insects14050473 - 17 May 2023

Cited by 1 | Viewed by 1227

Abstract

The quality of the host plant affects the life history parameters of tetranychid mites. The biology and fertility life tables of Tetranychus merganser on five host plants (Carica papaya, Phaseolus vulgaris, Capsicum annuum var. glabriusculum, Helietta parvifolia, and [...] Read more.

The quality of the host plant affects the life history parameters of tetranychid mites. The biology and fertility life tables of Tetranychus merganser on five host plants (Carica papaya, Phaseolus vulgaris, Capsicum annuum var. glabriusculum, Helietta parvifolia, and Rosa hybrida) were assessed under laboratory conditions at 28 ± 1 °C and 70–80% relative humidity (RH) with a photoperiod of 12:12 h (L:D). The development period of immature females differed among the tested host plants and ranged from 9.32 days on P. vulgaris to 11.34 days on H. parvifolia. For immature males, it ranged from 9.25 days on P. vulgaris to 11.50 days on H. parvifolia. The female survival rate varied from 53.97% on H. parvifolia to 94.74% on P. vulgaris. The highest total fecundity rate was recorded on P. vulgaris (125.40 eggs/female) and the lowest on H. parvifolia (43.92 eggs/female). The intrinsic rate of increase (rm) varied from 0.271 (H. parvifolia) to 0.391 (P. vulgaris). The net reproductive rate (R_O) was higher on P. vulgaris than on the other host plants. The longest mean generation time (GT) was calculated on C. annuum var. glabriusculum and the shortest on Rosa hybrida. The demographic parameters suggest the unsuitability of H. parvifolia as the host for the development of red spider mites, and the best performance of T. merganser was on P. vulgaris. Full article

(This article belongs to the Section Other Arthropods and General Topics)

11 pages, 2142 KiB

Open AccessArticle

Insecticidal Properties of Erythritol on Four Tropical Tephritid Fruit Flies, Zeugodacus cucurbitae, Ceratitis capitata, Bactrocera dorsalis, and B. latifrons (Diptera: Tephritidae)

by Dong H. Cha, Dominick Skabeikis, Bong-Soo Kim, Jana C. Lee and Man-yeon Choi

Insects 2023, 14(5), 472; https://doi.org/10.3390/insects14050472 - 16 May 2023

Cited by 3 | Viewed by 1369

Abstract

Tephritid fruit flies are among the most destructive agricultural pests of fruits and vegetables worldwide and can impose trade barriers against the movement of fresh tropical commodities. Primary pre-harvest control methods for these flies rely on the spraying of conventional chemical insecticides or [...] Read more.

Tephritid fruit flies are among the most destructive agricultural pests of fruits and vegetables worldwide and can impose trade barriers against the movement of fresh tropical commodities. Primary pre-harvest control methods for these flies rely on the spraying of conventional chemical insecticides or bait sprays. However, resistance to these control methods has been reported in fruit flies. Erythritol is a non-nutritive sugar alternative for human consumption, which has been tested and confirmed for its insecticidal properties against various insect pest species. In this study, using laboratory bioassays, we evaluated the insecticidal effect of erythritol alone or various erythritol formulations containing sucrose and/or protein on four tropical fruit fly species established in Hawaii (e.g., melon fly, Mediterranean fruit fly, oriental fruit fly, and Malaysian fruit fly). In addition, the effects of other non-nutritive hexose and pentose sugar alcohols, such as sorbitol, mannitol, and xylitol, were tested. Among the different standalone and combinatory treatments tested, 1M erythritol and a combinatory formulation of 2M erythritol + 0.5M sucrose appeared to be the most detrimental to the survival of all four species of tested flies, suggesting the potential of using erythritol as a non-toxic management tool for the control of tropical tephritid fruit flies. Full article

(This article belongs to the Special Issue Tephritid Fruit Flies (Diptera: Tephritidae): Biology, Ecology, and Integrated Management)

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20 pages, 12377 KiB

Open AccessArticle

Perianal Structures in Non-Myrmecophilous Aphids (Hemiptera, Aphididae)

by Natalia Kaszyca-Taszakowska, Mariusz Kanturski and Łukasz Depa

Insects 2023, 14(5), 471; https://doi.org/10.3390/insects14050471 - 16 May 2023

Viewed by 1041

Abstract

Mutualistic relation with ants is one of the leading features of aphid ecology. For some aphid species, it is a crucial association enhancing their survival capability, while the life mode of some others is completely independent of ants. It was broadly accepted that [...] Read more.

Mutualistic relation with ants is one of the leading features of aphid ecology. For some aphid species, it is a crucial association enhancing their survival capability, while the life mode of some others is completely independent of ants. It was broadly accepted that during the evolution of aphids, the ones relying on ants developed special morphological adaptations for this mutualism, the so-called trophobiotic organ. Its exact structuring, however, posed some explanatory difficulties because many non-myrmecophilous aphids had structural modifications accordant with the trophobiotic organ, while some myrmecophilous did not. Here we present an evaluation of the morphology of perianal structures in 25 non-myrmecophilous aphid species with reference to previous, similar studies on myrmecophilous species based on scanning electron microscopy. We conclude that the trophobiotic organ is an existing adaptation, but its definition requires revision. Full article

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11 pages, 1511 KiB

Open AccessFeature PaperArticle

Identification of Terpenoid Compounds and Toxicity Assays of Essential Oil Microcapsules from Artemisia stechmanniana

by Chang Liu, Zhilong Liu, Yihan Zhang, Xuan Song, Wenguang Huang and Rong Zhang

Insects 2023, 14(5), 470; https://doi.org/10.3390/insects14050470 - 16 May 2023

Viewed by 1199

Abstract

Plant essential oils, as biological pesticides, have been reviewed from several perspectives and play a key role in chemical ecology. However, plant essential oils show rapid degradation and vulnerability during actual usage. In this study, we conducted a detailed analysis of the compounds [...] Read more.

Plant essential oils, as biological pesticides, have been reviewed from several perspectives and play a key role in chemical ecology. However, plant essential oils show rapid degradation and vulnerability during actual usage. In this study, we conducted a detailed analysis of the compounds present in the essential oils of A. stechmanniana using gas chromatography–mass spectrometry (GC-MS). The results showed seventeen terpenoid compounds in the A. stechmanniana oil, with four major terpenoid compounds, i.e., eucalyptol (15.84%), (+)-2-Bornanone (16.92%), 1-(1,2,3-Trimethyl-cyclopent-2-enyl)-ethanone (25.63%), and (-)-Spathulenol (16.38%), in addition to an amount of the other terpenoid compounds (25.26%). Indoor toxicity assays were used to evaluate the insecticidal activity of Artemisia stechmanniana essential oil against Aphis gossypii, Frankliniella occidentalis, and Bactericera gobica in Lycium barbarum. The LC₅₀/LD₅₀ values of A. stechmanniana essential oils against A. gossypii, F. occidentalis, and B. gobica were 5.39 mg/mL, 0.34 mg/L, and 1.40 μg/insect, respectively, all of which were highly efficient compared with azadirachtin essential oil. Interestingly, A. stechmanniana essential oil embedded in β-cyclodextrin (microencapsule) remained for only 21 days, whereas pure essential oils remained for only 5 days. A field efficacy assay with the A. stechmanniana microencapsule (AM) and doses at three concentrations was conducted in Lycium barbarum, revealing that the insecticidal activities of AM showed high efficiency, maintained a significant control efficacy at all concentrations tested, and remained for 21 days. Our study identified terpenoid compounds from untapped Artemisia plants and designed a novel method against pests using a new biopesticide on L. barbarum. Full article

(This article belongs to the Section Insect Pest and Vector Management)

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17 pages, 4668 KiB

Open AccessArticle

Expression Profile, Regulatory Network, and Putative Role of microRNAs in the Developmental Process of Asian Honey Bee Larval Guts

by Xiaoxue Fan, Wende Zhang, Sijia Guo, Leran Zhu, Yiqiong Zhang, Haodong Zhao, Xuze Gao, Haibin Jiang, Tianze Zhang, Dafu Chen, Rui Guo and Qingsheng Niu

Insects 2023, 14(5), 469; https://doi.org/10.3390/insects14050469 - 16 May 2023

Cited by 3 | Viewed by 1158

Abstract

MiRNAs, as a kind of key regulators in gene expression, play vital roles in numerous life activities from cellular proliferation and differentiation to development and immunity. However, little is known about the regulatory manner of miRNAs in the development of Asian honey bee [...] Read more.

MiRNAs, as a kind of key regulators in gene expression, play vital roles in numerous life activities from cellular proliferation and differentiation to development and immunity. However, little is known about the regulatory manner of miRNAs in the development of Asian honey bee (Apis cerana) guts. Here, on basis of our previously gained high-quality transcriptome data, transcriptome-wide identification of miRNAs in the larval guts of Apis cerana cerana was conducted, followed by investigation of the miRNAs’ differential expression profile during the gut development. In addition to the regulatory network, the potential function of differentially expressed miRNAs (DEmiRNAs) was further analyzed. In total, 330, 351, and 321 miRNAs were identified in the 4-, 5-, and 6-day-old larval guts, respectively; among these, 257 miRNAs were shared, while 38, 51, and 36 ones were specifically expressed. Sequences of six miRNAs were confirmed by stem-loop RT-PCR and Sanger sequencing. Additionally, in the “Ac4 vs. Ac5” comparison group, there were seven up-regulated and eight down-regulated miRNAs; these DEmiRNAs could target 5041 mRNAs, involving a series of GO terms and KEGG pathways associated with growth and development, such as cellular process, cell part, Wnt, and Hippo. Comparatively, four up-regulated and six down-regulated miRNAs detected in the “Ac5 vs. Ac6” comparison group and the targets were associated with diverse development-related terms and pathways, including cell, organelle, Notch and Wnt. Intriguingly, it was noticed that miR-6001-y presented a continuous up-regulation trend across the developmental process of larval guts, implying that miR-6001-y may be a potential essential modulator in the development process of larval guts. Further investigation indicated that 43 targets in the “Ac4 vs. Ac5” comparison group and 31 targets in the “Ac5 vs. Ac6” comparison group were engaged in several crucial development-associated signaling pathways such as Wnt, Hippo, and Notch. Ultimately, the expression trends of five randomly selected DEmiRNAs were verified using RT-qPCR. These results demonstrated that dynamic expression and structural alteration of miRNAs were accompanied by the development of A. c. cerana larval guts, and DEmiRNAs were likely to participate in the modulation of growth as well as development of larval guts by affecting several critical pathways via regulation of the expression of target genes. Our data offer a basis for elucidating the developmental mechanism underlying Asian honey bee larval guts. Full article

(This article belongs to the Section Insect Molecular Biology and Genomics)

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12 pages, 8713 KiB

Open AccessArticle

Secondary Rhinaria Contribute to Major Sexual Dimorphism of Antennae in the Aphid Semiaphis heraclei (Takahashi)

by Ke-Xin Song, Jiang-Yue Wang, Hai-Li Qiao, Hong-Shuang Wei, Kun Guo and Chang-Qing Xu

Insects 2023, 14(5), 468; https://doi.org/10.3390/insects14050468 - 16 May 2023

Viewed by 1198

Abstract

Sexual generation is an important generation in the life cycle of host-alternating aphids, and its population size determines the intensity of the peak in the next spring. Although male trapping techniques based on olfactory stimuli have been successfully established in the field, the [...] Read more.

Sexual generation is an important generation in the life cycle of host-alternating aphids, and its population size determines the intensity of the peak in the next spring. Although male trapping techniques based on olfactory stimuli have been successfully established in the field, the biological basis of olfactory perception in males is unclear. In this study, we compared the morphology of antennae and the types, sizes, numbers, and distribution of sensilla between males and sexual females in the host-alternating aphid Semiaphis heraclei (Hemiptera: Aphididae). We found that flagellum length differentiation contributed to the majority of the sexual dimorphism of antennae. Most sensillum types or subtypes, including trichoid sensilla subtype I, campaniform sensilla, and primary rhinaria subtypes I and II, were enlarged in males. In addition, males bore more trichoid sensilla subtype I than sexual females. In particular, secondary rhinaria were present in males only and could not be detected in sexual females. These results revealed the structural basis of male olfactory perception. Our findings provide insight into the mechanism underlying chemical communication between sexual aphids and could thus be useful for pest control. Full article

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16 pages, 1633 KiB

Open AccessArticle

Forensic DNA Analysis of Mixed Mosquito Blood Meals: STR Profiling for Human Identification

by Ashraf Mohamed Ahmed, Amani Mohammed Alotaibi, Wedad Saeed Al-Qahtani, Frederic Tripet and Sayed Amin Amer

Insects 2023, 14(5), 467; https://doi.org/10.3390/insects14050467 - 16 May 2023

Cited by 1 | Viewed by 3181

Abstract

Mosquito vectors captured at a crime scene are forensically valuable since they feed on human blood, and hence, human DNA can be recovered to help identify the victim and/or the suspect. This study investigated the validity of obtaining the human short tandem repeats [...] Read more.

Mosquito vectors captured at a crime scene are forensically valuable since they feed on human blood, and hence, human DNA can be recovered to help identify the victim and/or the suspect. This study investigated the validity of obtaining the human short tandem repeats (STRs) profile from mixed blood meals of the mosquito, Culex pipiens L. (Diptera, Culicidae). Thus, mosquitoes were membrane-feed on blood from six different sources: a human male, a human female, mixed human male-female blood, mixed human male-mouse blood, mixed human female-mouse blood, and mixed human male-female-mouse blood. DNA was extracted from mosquito blood meals at 2 h intervals up to 72 h post-feeding to amplify 24 human STRs. Data showed that full DNA profiles could be obtained for up to 12 h post-feeding, regardless of the type of blood meal. Complete and partial DNA profiles were obtained up to 24 h and 36 h post-feeding, respectively. The frequencies of STR loci decreased over time after feeding on mixed blood until they became weakly detectable at 48 h post-feeding. This may indicate that a blood meal of human blood mixed with animal blood would contribute to maximizing DNA degradation and thus affects STR identification beyond 36 h post-feeding. These results confirm the feasibility of human DNA identification from mosquito blood meals, even if it is mixed with other types of non-human blood, for up to 36 h post-feeding. Therefore, blood-fed mosquitoes found at the crime scene are forensically valuable, as it is possible to obtain intact genetic profiles from their blood meals to identify a victim, a potential offender, and/or exclude a suspect. Full article

(This article belongs to the Section Role of Insects in Human Society)

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11 pages, 2399 KiB

Open AccessArticle

Lymantria Dispar Iflavirus 1 RNA Comprises a Large Proportion of RNA in Adult L. dispar Moths

by Michael E. Sparks, Yi-Ming Wang, Juan Shi and Robert L. Harrison

Insects 2023, 14(5), 466; https://doi.org/10.3390/insects14050466 - 15 May 2023

Viewed by 1075

Abstract

The spongy moth virus Lymantria dispar iflavirus 1 (LdIV1), originally identified from a Lymantria dispar cell line, was detected in 24 RNA samples from female moths of four populations from the USA and China. Genome-length contigs were assembled for each population and compared [...] Read more.

The spongy moth virus Lymantria dispar iflavirus 1 (LdIV1), originally identified from a Lymantria dispar cell line, was detected in 24 RNA samples from female moths of four populations from the USA and China. Genome-length contigs were assembled for each population and compared with the reference genomes of the first reported LdIV1 genome (Ames strain) and two LdIV1 sequences available in GenBank originating from Novosibirsk, the Russian Federation. A whole-genome phylogeny was generated for these sequences, indicating that LdIV1 viruses observed in North American (flightless) and Asian (flighted) spongy moth lineages indeed partition into clades as would be expected per their host’s geographic origin and biotype. A comprehensive listing of synonymous and non-synonymous mutations, as well as indels, among the polyprotein coding sequences of these seven LdIV1 variants was compiled and a codon-level phylogram was computed using polyprotein sequences of these, and 50 additional iflaviruses placed LdIV1 in a large clade consisting mostly of iflaviruses from other species of Lepidoptera. Of special note, LdIV1 RNA was present at very high levels in all samples, with LdIV1 reads accounting for a mean average of 36.41% (ranging from 1.84% to 68.75%, with a standard deviation of 20.91) of the total sequenced volume. Full article

(This article belongs to the Topic Host–Parasite Interactions)

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16 pages, 5593 KiB

Open AccessFeature PaperArticle

Research on Photoinduction-Based Technology for Trapping Asian Longhorned Beetle (Anoplophora glabripennis (Motschulsky, 1853) (Coleoptera: Cerambycidae)

by Xianglan Jiang, Xiaoxia Hai, Yongguo Bi, Feng Zhao, Zhigang Wang and Fei Lyu

Insects 2023, 14(5), 465; https://doi.org/10.3390/insects14050465 - 15 May 2023

Cited by 1 | Viewed by 1103

Abstract

Light traps play a crucial role in monitoring pest populations. However, the phototactic behavior of adult Asian longhorned beetle (ALB) remains enigmatic. To provide a theoretical foundation to select the suitable light emitting diode (LED)-based light sources used for monitoring ALB, we compared [...] Read more.

Light traps play a crucial role in monitoring pest populations. However, the phototactic behavior of adult Asian longhorned beetle (ALB) remains enigmatic. To provide a theoretical foundation to select the suitable light emitting diode (LED)-based light sources used for monitoring ALB, we compared the effect of exposure time on the phototactic response rates of adults at wavelengths of 365 nm, 420 nm, 435 nm, and 515 nm, and found that the phototactic rate increased gradually when the exposure time was prolonged, but there was no significant difference between different exposure times. We evaluated the effect of diel rhythm and found the highest phototactic rate at night (0:00–2:00) under 420 nm and 435 nm illumination (74–82%). Finally, we determined the phototactic behavioral response of adults to 14 different wavelengths and found both females and males showed a preference for violet wavelengths (420 nm and 435 nm). Furthermore, the effect of the light intensity experiments showed that there were no significant differences in the trapping rate between different light intensities at 120 min exposure time. Our findings demonstrate that ALB is a positively phototactic insect, showing that 420 nm and 435 nm are the most suitable wavelengths for attracting adults. Full article

(This article belongs to the Special Issue Managing Invasive Insects: Good Intentions, Hard Realities)

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16 pages, 5785 KiB

Open AccessArticle

In Vitro Evaluation of the Antibacterial Activity of the Peptide Fractions Extracted from the Hemolymph of Hermetia illucens (Diptera: Stratiomyidae)

by Carmen Scieuzo, Fabiana Giglio, Roberta Rinaldi, Marilena E. Lekka, Flora Cozzolino, Vittoria Monaco, Maria Monti, Rosanna Salvia and Patrizia Falabella

Insects 2023, 14(5), 464; https://doi.org/10.3390/insects14050464 - 15 May 2023

Cited by 11 | Viewed by 2338

Abstract

Antimicrobial peptides (AMPs) are a chemically and structurally heterogeneous family of molecules produced by a large variety of living organisms, whose expression is predominant in the sites most exposed to microbial invasion. One of the richest natural sources of AMPs is insects which, [...] Read more.

Antimicrobial peptides (AMPs) are a chemically and structurally heterogeneous family of molecules produced by a large variety of living organisms, whose expression is predominant in the sites most exposed to microbial invasion. One of the richest natural sources of AMPs is insects which, over the course of their very long evolutionary history, have adapted to numerous and different habitats by developing a powerful innate immune system that has allowed them to survive but also to assert themselves in the new environment. Recently, due to the increase in antibiotic-resistant bacterial strains, interest in AMPs has risen. In this work, we detected AMPs in the hemolymph of Hermetia illucens (Diptera, Stratiomyidae) larvae, following infection with Escherichia coli (Gram negative) or Micrococcus flavus (Gram positive) and from uninfected larvae. Peptide component, isolated via organic solvent precipitation, was analyzed by microbiological techniques. Subsequent mass spectrometry analysis allowed us to specifically identify peptides expressed in basal condition and peptides differentially expressed after bacterial challenge. We identified 33 AMPs in all the analyzed samples, of which 13 are specifically stimulated by Gram negative and/or Gram positive bacterial challenge. AMPs mostly expressed after bacterial challenge could be responsible for a more specific activity. Full article

(This article belongs to the Special Issue Insects and Their Derivatives for Human Practical Uses (Volume II))

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13 pages, 1700 KiB

Open AccessArticle

Digestive Characteristics of Hyphantria cunea Larvae on Different Host Plants

by Aoying Zhang, Tao Li, Lisha Yuan, Mingtao Tan, Dun Jiang and Shanchun Yan

Insects 2023, 14(5), 463; https://doi.org/10.3390/insects14050463 - 14 May 2023

Cited by 5 | Viewed by 1198

Abstract

Digestive physiology mediates the adaptation of phytophagous insects to host plants. In this study, the digestive characteristics of Hyphantria cunea larvae feeding preferences on different host plants were investigated. The results showed that the body weight, food utilization, and nutrient contents of H. [...] Read more.

Digestive physiology mediates the adaptation of phytophagous insects to host plants. In this study, the digestive characteristics of Hyphantria cunea larvae feeding preferences on different host plants were investigated. The results showed that the body weight, food utilization, and nutrient contents of H. cunea larvae feeding on the high-preference host plants were significantly higher than those feeding on the low-preference host plants. However, the activity of larval digestive enzymes in different host plants presented an opposite trend, as higher α-amylase or trypsin activity was observed in the group feeding on the low-preference host plants than that feeding on the high-preference host plants. Upon treatment of leaves with α-amylase and trypsin inhibitors, the body weight, food intake, food utilization rate, and food conversion rate of H. cunea larvae significantly decreased in all host plant groups. Furthermore, the H. cunea comprised highly adaptable compensatory mechanisms of digestion involving digestive enzymes and nutrient metabolism in response to digestive enzyme inhibitors. Taken together, digestive physiology mediates the adaptation of H. cunea to multiple host plants, and the compensatory effect of digestive physiology is an important counter-defense strategy implemented by H. cunea to resist plant defense factors, especially the insect digestive enzyme inhibitors. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

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20 pages, 437 KiB

Open AccessReview

Four Most Pathogenic Superfamilies of Insect Pests of Suborder Sternorrhyncha: Invisible Superplunderers of Plant Vitality

by Volodymyr V. Oberemok, Nikita V. Gal’chinsky, Refat Z. Useinov, Ilya A. Novikov, Yelizaveta V. Puzanova, Roman I. Filatov, Nanan J. Kouakou, Kra F. Kouame, Kouadio D. Kra and Kateryna V. Laikova

Insects 2023, 14(5), 462; https://doi.org/10.3390/insects14050462 - 13 May 2023

Cited by 4 | Viewed by 2203

Abstract

Sternorrhyncha representatives are serious pests of agriculture and forestry all over the world, primarily causing damage to woody plants. Sternorrhyncha members are vectors for the transfer of a large number of viral diseases, and subsequently, the host plant weakens. Additionally, many are inherent [...] Read more.

Sternorrhyncha representatives are serious pests of agriculture and forestry all over the world, primarily causing damage to woody plants. Sternorrhyncha members are vectors for the transfer of a large number of viral diseases, and subsequently, the host plant weakens. Additionally, many are inherent in the release of honeydew, on which fungal diseases develop. Today, an innovative approach is needed to create new and effective ways to control the number of these insects based on environmentally friendly insecticides. Of particular relevance to such developments is the need to take into account the large number of organisms living together with insect pests in this group, including beneficial insects. Practically without changing their location on their host plant, they adopted to be more invisible and protected due to their small size, symbiosis with ants, the ability to camouflage with a leaf, and moderately deplete plants and others, rarely leading them to death but still causing substantial economic loss in the subtropics and tropics. Due to the lack of presence in the literature, this review fills in this pesky spot by examining (on the example of distinct species from four superfamilies) the characteristic adaptations for this suborder and the chemical methods of combating these insects that allow them to survive in various environmental conditions, suggesting new and highly promising ways of using olinscides for plant protection against Sternorrhyncha members. Full article

(This article belongs to the Special Issue Managing Invasive Insects: Good Intentions, Hard Realities)

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11 pages, 8415 KiB

Open AccessArticle

The Mouthparts of Female Blood-Feeding Frog-Biting Midges (Corethrellidae, Diptera)

by Stephan Barton, Jonas Virgo and Harald W. Krenn

Insects 2023, 14(5), 461; https://doi.org/10.3390/insects14050461 - 13 May 2023

Cited by 1 | Viewed by 1713

Abstract

Females of frog-biting midges (Corethrellidae) obtain their blood meals from male calling frogs. While the morphology of the feeding apparatus is well studied in hematophagous Diptera that impact humans, frog-biting midges have received far less attention. We provide a detailed micromorphological examination of [...] Read more.

Females of frog-biting midges (Corethrellidae) obtain their blood meals from male calling frogs. While the morphology of the feeding apparatus is well studied in hematophagous Diptera that impact humans, frog-biting midges have received far less attention. We provide a detailed micromorphological examination of the piercing blood-sucking proboscis and maxillary palpus in three Corethrella species using scanning electron microscopy and histological semi-thin sectioning. We also compare the sensilla found on the proboscis tip and the palpus of Corethrella with other piercing blood-sucking Diptera. Corethrella spp. have a proboscis length of about 135 µm, equipped with delicate mandibular piercing structures composing the food canal together with the labrum and hypopharynx. Their proboscis composition is plesiomorphic and more similar to other short-proboscid hematophagous Culicomorpha (e.g., Simuliidae), in contrast to the phylogenetically more closely related long-proboscid Culicidae. As in other short-proboscid taxa, the salivary canal in Corethrella spp. transitions into an open salivary groove with one mandible forming a seal, whereas in Culicidae the salivary canal is closed until the tip of the proboscis. We discuss the possible functional constraints of very short, piercing blood-sucking proboscises (e.g., dimensions of host blood cells) that may limit the size of the food canal. Full article

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15 pages, 2036 KiB

Open AccessArticle

Effects of Irradiation on Biology and Mating Behaviour of Wild Males of Brown Marmorated Stink Bug Using a 6 MV Medical Linear Accelerator

by Gerardo Roselli, Gianfranco Anfora, David Maxwell Suckling, Valerio Mazzoni, Valentina Vanoni, Loris Menegotti, Lorenzo Fellin, Marco Valerio Rossi Stacconi, Claudio Ioriatti and Massimo Cristofaro

Insects 2023, 14(5), 460; https://doi.org/10.3390/insects14050460 - 13 May 2023

Cited by 3 | Viewed by 1521

Abstract

The brown marmorated stink bug, Halyomorpha halys, is a pentatomid bug of Eastern Asian origin that became an economically relevant pest in the Eurasian and American continents. Management of this species is limited to use of chemical insecticides: an inefficient method due [...] Read more.

The brown marmorated stink bug, Halyomorpha halys, is a pentatomid bug of Eastern Asian origin that became an economically relevant pest in the Eurasian and American continents. Management of this species is limited to use of chemical insecticides: an inefficient method due to the strong adaptability of the target pest. The sterile insect technique (SIT) is potentially a valid tactic in the search for nontoxic alternatives. In this work, we investigated the suitability of mass-trapped overwintering males, collected during the aggregation phase before the winter diapause, for their release as competitive sterile males in an SIT programme. Differently from previous studies, irradiation was applied with a linear accelerator device that produced high-energy photons. Following a similar scientific protocol with newly emerged irradiated males, the effects of X-ray irradiation on physiological parameters (longevity, fecundity and fertility) were assessed. In addition, behavioural bioassays were carried out in no-choice conditions to evaluate if irradiation interferes with mating processes. The results are very encouraging; the effects of the irradiation at 32 Gy did not differ from the controls in the longevity or fecundity of the exposed overwintering adults. The hatching rate of the eggs laid by the fertile females that had mated with the irradiated males was less than 5%. The results of behavioural bioassays showed that the irradiation did not cause a significant impact on the quality of the sterile males. More research is warranted to evaluate the mating competitiveness of sterile males in semi-field and field conditions. Full article

(This article belongs to the Section Insect Pest and Vector Management)

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16 pages, 3359 KiB

Open AccessArticle

Allelochemical Interactions in the Trophic System «Henosepilachna vigintioctomaculata Motschulsky—Solanum tuberosum Linneus»

by Nathalia Valerievna Matsishina, Marina Vladimirovna Ermak, Irina Vyacheslavovna Kim, Petr Viktorovich Fisenko, Olga Abdulalievna Sobko, Alexey Grigorievich Klykov and Alexey Nikolaevich Emel’yanov

Insects 2023, 14(5), 459; https://doi.org/10.3390/insects14050459 - 13 May 2023

Viewed by 925

Abstract

Henosepilachna vigintioctomaculata is an intrinsic element in the agroecosystem of potato fields. The issues of relationships in the system “potato ladybird beetle—potato plant” have not yet been studied. To study the effect of potato varieties on the potato ladybird beetle, only hatched and [...] Read more.

Henosepilachna vigintioctomaculata is an intrinsic element in the agroecosystem of potato fields. The issues of relationships in the system “potato ladybird beetle—potato plant” have not yet been studied. To study the effect of potato varieties on the potato ladybird beetle, only hatched and active larvae with a hatching rate close to 100% were selected from a laboratory colony. Larvae of the first summer generation collected in potato fields were used in our study to determine the level of adrenaline in the bodies of insects, fresh potato leaves were used to study the content of glycoalkaloids, the content and activity of proteinase inhibitors. The larvae that fed on plants of varieties Belmonda, Queen Anne, Lilly, Dachny, Kazachok, Yubilyar, and Avgustin demonstrated the highest level of stress while the stress level in those that fed on variety Smak was the lowest. The damage inflicted by potato ladybird beetles on leaves of some studied potato varieties led to a progressive increase in the content of glycoalkaloids already within 24 h after the phytophages had been transferred. In most cases, the content of glycoalkoloids increased by 20% within five days. Potato ladybird beetles feeding on plants of different potato varieties caused a progressive increase in proteinase inhibitors (% of the control). Plants of variety Smak did not show a significant increase in the content of alkaloids in the herbage in response to the damage. A correlation was established between the mortality rate, the activity of proteinase inhibitors, the dynamics of glycoalkaloids, and the level of adrenaline, which could be formulated as follows: the higher the content of glycoalkaloids and the activity of proteinase inhibitors in the tissues of potato plants, the higher the level of stress in the potato ladybird beetles that feed on them. Full article

(This article belongs to the Section Insect Pest and Vector Management)

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12 pages, 2407 KiB

Open AccessArticle

Predicting the Current and Future Distributions of Frankliniella occidentalis (Pergande) Based on the MaxEnt Species Distribution Model

by Zhiling Wang, Danping Xu, Wenkai Liao, Yan Xu and Zhihang Zhuo

Insects 2023, 14(5), 458; https://doi.org/10.3390/insects14050458 - 12 May 2023

Cited by 7 | Viewed by 1682

Abstract

Climate change has a highly significant impact on the distribution of species. As the greenhouse effect intensifies each year, the distribution of organisms responds to this challenge in diverse ways. Therefore, climatic environmental variables are a key entry point for capturing the current [...] Read more.

Climate change has a highly significant impact on the distribution of species. As the greenhouse effect intensifies each year, the distribution of organisms responds to this challenge in diverse ways. Therefore, climatic environmental variables are a key entry point for capturing the current and future distribution trends of pests. Frankliniella occidentalis is an invasive pest attested worldwide. Its damage is mainly divided into two aspects, including mechanical damage caused by its feeding and egg laying and the spread of tomato spotted wilt virus (TSWV). TSWV is the most dominant transmitted virulent disease. Moreover, F. occidentalis is the major vector for the transmission of this virus, which poses a grave threat to the yield and survival of our crops. In this study, the distribution pattern of this pest was explored using 19 bioclimatic variables based on the Maxent model. The results indicated that in the future, high-suitability areas of F. occidentalis will be widely distributed in 19 provinces of China, with Hebei, Henan, Shandong, Tianjin and Yunnan being the most abundant. Among the 19 bioclimatic variables, the five variables of annual mean temperature (Bio 1), temperature seasonality (standard deviation × 100) (Bio 4), min temperature of the coldest month (Bio 6), mean temperature of the driest quarter (Bio 9) and precipitation of the coldest quarter (Bio 19) were selected as the key environmental variables affecting the distribution of F. occidentalis. In summary, temperature and precipitation are vital factors for the study of the species’ distribution, and this study aims to provide new perspectives for the control of this pest in China. Full article

(This article belongs to the Special Issue Climate Change and Insects)

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Insects, Volume 14, Issue 5 (May 2023) – 83 articles

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